Impact tool



M.- P. RAINEY A ril 1, 1969 IMPACT TOOL Filed June 26 1967 INVENTOR W/ansaan f? Pa/hey I $7 BY ORNEYS United States Patent O ABSTRACT OF THE DISCLOSURE A hand tool comprising a tube interconnected to a shaft for relative reciprocation along the rotation about the axis of the shaft. A tubular connecting member is rotatable and reciprocable on the shaftand cooperates with cam and shoulder surfaces onthe tube and shaft, respectively, to rotate the tubewhen the shaft-is rotated and to rotate the tubewhen a force is applied longitudinally of the shaft. 6 t

This invention relates to hand tools and, more particularly, to a tool for mining objects such as screws, other fasteners or the like. i i

Objects such as screws or bolts which have been installed for relatively long periods of time or under certain environmental conditions may become rusted, corroded or otherwise tightly engaged and difficult to remove. Oftenit is necessary to apply impactive force to the object to overcornethe initial resistance to turning. Similarly, it -is sometimes desirable to apply impactive force to such an object at the end of the installation operation in order to seat the object with adequate force to meet certain specifications. t i i i Impactive tools operated by air or electricity have been provided. These tools are bulky, expensive, and are not adaptable for use apart for the application of impractive forces. The saparate power sources which conventional tools of this kind require further limit their practical use. 6 V

Accordingly, it is the primary object of this invention to provide a tool which may be used in the manner of an ordinary screwdriver, wrench or the like, yetwhich is also capable of imparting impactive turning forces to an object and in whatever direction may bedesired.

It is another important object of -the--invention to provide a simple, inexpensive, rugged and-completely portable tool capable-of use to impactivelyloosen or tighten screws, nuts or the like. i t e i i It is another very important object of the instant inveniton to provide a screwdriver-type tool which can safely remove tight fasteners such as screws without scarring or damaging the kerfed head of the fastener.

A still further object of the invention is to provide a tool constructed in a manner whereby the-components subject to theli greatest stresses are constructed in a manner for best bearing the stresses. 6 a e Another object of the invention is to provide a tool having components'which are locked to impart turning motion to an object when memo] is rotated, yet which automatically assume relative positions to impart turning in the direction of saidtorque when an impactive force is applied tothe tool. i r.

A yet further object of this invention is to provide a tool of thiskind which isextremely versatile and which may accommodate a variety of fastenersor-otherobjects tobeturned. l 3; These and other important objects of the present invention will be further explained or will become apparent from the following description, claims and drawing. Inthe drawing. i it FIGURE -1 is a side elevational view of an impact ice tool constructed pursuant to the principles of this invention, with a screwdriver head affixed to the tool;

FIG. 2 is .a fragmentary view similar to FIG. 1 but.

illustrating the relative positions of the components when the tool is torqued in one direction on its longitudinal,

axis;

no.4 is a view similar to FIG} but Hankerin the relative positions of the components when the tool is torqued in the opposite direction;

FIG. .5 is an enlarged, detailed,cross-sectional view taken along line 5--5 of FIG.- 2; and

FIG. 6 is a cross-sectional viewtaken along line 6-6.

of FIG. 3. r o

A tool embodying the'principles of this invention ls broadly designated 10 in the drawings and comprsies an elongated shaft 12 extending in telescoped relationship into the bore 14 of an elongated tube 16. An enlargement 18of bore 14 at one end of tube 16 receives a fastene 20 for shaft 12. i In the embodiment illustrated, fastener 20 comprises,

a nut received in threaded relationship on one end of shaft 12. Fastener 20 cooperates with. a washer 22 to limit relative rectilinear movement between shaft 12 and tube 16 by engagement of washer 22 against the annular shoulder 24 between enlargement 18 and bore 14.

The outermost end of tube 16 is closed by aplug having a transversely polygonal projection 28 adapted to receive a screwdriver 30 orthe like as illustrated in FIG. 1.-In this respect, screwdriver 30 may be provided with a socket end 32 adapted to be received overprojection 28 as is conventional to permit selective installa:

tion and removal-of any of a variety of objects to be driven by tool 10 through the plug or driver 26 as will be hereinafter explained. I

A coil spring 34 is received in enlargement 18 interposed between plug 26 and fastener 20 for yieldably maintaining tube 16 and shaft 12 in the positions illustrated with washer 22 seated upon annular shoulder 24.

The opposite end of shaft 12 may be conveniently pro-. vided -withaa handle 36 which is rigidlysecured to shatf 12 to permitmanual turning of the latter by, application of torque to handle 36 in the usual manner. A collar 38 surrounding shaft 12 adjacent the end of handle 36 is rigidly securedtoshaft 12 by screvv thread means 40,

and a fastener 41. 7 H p A tubular member 42 is telescoped over shaft 12 and is both shiftable and rotatable on the latter. Member 42 is interposed between the proximal ends: of collar 38 and tube 16. Member 42 is provided with a pair of shoulders 44 and 46 at one end of the member as illustrated in FIGS. 1 and2 of the drawing. The shoulder 44 is on the opposite side of member 42from shoulder 46 and identical to curvilinear cam surfaces 48 and 50 are interposed between the shoulders 44 and 46. The proximal end of tube 16 is provided with a shoulder 52 disposedin opposed, facing relationship to shoulder 44, and a similar shoulder (not shown) is disposed in facing relationship" to shouder 46 of member 42. Similarly, tube 16 has curvilinear cam surfaces .54 and 56 disposed in complemental opposed relationship to cam surfaces 48 and 50 respectively.

The opposite end of member 42 is constructed to be.

Whereas the ends of tube l6 and collar 38, respectively,

3 are shaped for complemental engagement with the corresponding ends of member 42, tube 16 and collar 38 are spaced apart sufficiently to permit longitudinal shifting of member 42 into and out of engagement with the corresponding cam and shoulder surfaces for a purpose to be hereinafter described.

In operation, a screwdriver or similar unit is attached to projection 28 and the screwdriver is engaged on the object to be driven. Rotational torque may be applied to handle 36 as is conventional. Referring to FIG. 3, if torque is applied in the direction of the arrow 72, the engagement of cam surfaces 58 and 60 of collar 38 with the corresponding cam surfaces 62 and 64 of member 42 causes the latter to shift longitudinally along the axis of shaft 12 and into engagement with the proximal end of tube 16 as is illustrated. The interengagement of the curvilinear cam and shoulder surfaces of the embracing ends of member 42 and tube 16, lock the same together so that rotational forces in the direction of arrow 72 are imparted to tube 16 and consequently to the object to be turned. Tool 10 may thus be utilized in the manner of a conventional screwdriver.

With the components in the positions illustrated in FIG. 3, however, the application of an axially directed force as is represented by the phantom arrow 74 shifts shaft 12 within bore 14 causing the facing cam surfaces 58 and 62 and 60 and 64 respectively, to slide upon one another. This imparts relative rotation between tube 16 and shaft 12 in the direction of arrow 72. Thus, assuming that a screw is being tightened by tool 10, the final turning of the screw may be effected by a blow applied axially of shaft 12 upon handle 36. Thus, the final turning of the screw may be accomplished impactively to assure a firm seating of the screw.

Conversely, and referring now to FIG. 4, the application of a rotational torque in the direction of the arrow 76 automatically causes a shifting of member 42 longitudinally along shaft 12 toward handle 36 under the influence of the sliding of the opposed cam surfaces 48 and 54 and 50 and 56, respectively. This brings the opposite end of member 42 into locked and embracing relationship to the proximal end of collar 38 as is illustrated in FIG. 4. It will be noted that the opposed shoulders of tube 16 and the corresponding end of member 42, are now in position so that a force applied axially of shaft 12 will impart a rotative force to tube 16. This time, however, the relative rotation of tube 16 is in the direction of the arrow 76. Thus, tool 10 may be utilized for loosening a screw through the application of an impactive force to handle 36. The relative rotation of tube 16 which is imparted to the screw will also be impactive and have a tendency to readily loosen rust, corrosion or other forces tending to resist removal of the screw.

It should also be pointed out that the use of tool 10 will minimize scarring or other injury to the head of the screw or other fastener since the rotative forces imparted by tool 10 may also be accompanied by longitudinal forces tending to hold the tool against the screw. Thus, the tool cannot slip away from the kerf or head of the fastener which is the primary cause of damage occasioned by attempts to remove a frozen screw or the like.

It will be apparent to those skilled in the art that the principles of this invention to impactively apply a rotative force for turning an object could be accomplished by the member 42 having only one end configured as illustrated to complementally engage tube 16. In that event member 42 could be rigid to shaft 12 and collar 38 could be eliminated. Consequently, the relative rotation of tube 16 with respect to shaft 12 derived by an impactive force on handle 36 would be in one direction only, rather than in the direction of the application of torque to shaft 12 as is possible in the embodiment illustrated. Manifestly, the direction of such relative rotation would depend upon the configuration of the interengaging cam surfaces and shoulders as will be apparent.

While tool 10 has been described primarily for use as a screwdriver, and it is apparent that a wide variety of screwdriver bits may be utilized therewith, it is also contemplated that any of a number of objects could be advantageously turned by tool 10. Accordingly, conventional socket wrenches of any size or shape might be affixed to projection 28 whereupon the installation or removal of nuts could be accomplished by rotation of handle 36 and by an impact directed longitudinally of shaft 12 on handle 36. Further, plug 26 could be eliminated and the outermost end of tube 16 shaped for engaging an object to be driven as will be understood by those skilled in the art.

The yieldable means such as spring 34 at the end of shaft 12 serves to maintain the proper spacing between the proximal ends of tube 16 and collar 38 which is slightly greater than the length of member 42. Spring 34, however, yields upon relative rectilinear shifting of the elements 12 and 16 for transmission of the impactive rotational force on tube 16 as has heretofore been explained.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a tool for turning an object:

a pair of elongated elements having their longitudinal axes in alignment and each element having a cam surface;

means interconnecting the elements for relative rotation about said axes and relative rectilinear reciprocation along said axes; and

transmission means between the elements having structure for imparting rotative movement to one of the elements upon rectilinear movement of the other elements in one direction or upon rotation of said other element,

said transmission means including a member shiftable along a predetermined path of travel and having opposed cam surfaces,

each of the cam surfaces on said elements being engageable with and complemental to a corresponding cam surface on the member,

said member being operable upon said rectilinear movement of the other element for rotating the one element in one direction when the member is at one end of its path of travel and in the opposite direction when the member is at the opposite end of its path of travel.

2. The invention of claim 1, wherein said member is rotatable and reciprocable on said other element.

3. The invention of claim 2, wherein is provided a first pair of opposed shoulders, one on the member and one on said one element, and a second pair of shoulders, one on the member and one on said other element, the first pair being disposed for interengagement to impart rotation in one direction and the other pair being disposed for interengagement to impart rotation in the opposite direction.

4. A tool for rotating objects, comprising:

an elongated shaft;

a tube telescoped over one end of the shaft, said shaft being shiftable along and rotatable about the longitudinal axis of the tube;

a driver carried by the tube and adapted to drivingly engage said object to be rotated;

first cam means on the shaft;

second cam means on the tube;

a cam member interposed between said first and second cam means; and

interengageable shoulder means between the member and the shaft and between the member and the tube, said cam member having a pair of oppositely inclined surfaces, said surfaces being disposed to cooperate with said first and second cam means upon the application of a rotational torque to said shaft to align one of said surfaces with a corresponding cam means whereby a longitudinal force on the other end of 5 said shaft rotates said tube and driver in the direction of said torque. 5. The invention of claim 4 wherein said shaft is shiftably mounted for reciprocation along a predetermined path of travel parallel to the longitudinal axis of the tube, and wherein is included resilient means between the 5 tube and the shaft for yieldably biasing the latter toward one end of its shiftable path of travel.

6. The invention of claim 4, wherein said member is rotatably and reciprocably carried by the shaft in surrounding relationship thereto.

7. The invention of claim 6, wherein is provided a collar on the shaft, the cam means and the shoulder means of the shaft being on the collar, said member being tubular and interposed between the collar and the tube.

6 References Cited UNITED STATES PATENTS 811,348 1/1906 Wolf 81-52.3 1.742,040 12/1929 Lynch et al l4550 X 2,559,558 7/1951 Carlson et al. 173-93.7 X 2,633,042 3/ 1953 Halverson 145-61.4 X

FOREIGN PATENTS 10,256 5/1934 Australia.

10 ROBERT C. RIORDON, Primary Examiner.

R. V. PARKER, 11L, Assistant Examiner.

US. Cl. X.R. 

